A new foot structure with springs and flat soles for biped robot walking

This paper presents a new robotic foot structure for biped walking on rough terrain. Because it is difficult to detect the detailed geometry and dynamic properties of the ground surface before a walking robot lands on it, a foot structure with point contact links has been proposed by the authors to adapt to the ground surface with various geometry and hardness. However, due to the point contact structure, the foot sinks into a soft ground and slides from a small stone-like protrusion on the ground. This study replaces the point contact links by movable flat soles for considering the above problems. In addition, a landing controller is applied to the proposed foot for increasing the stability of contact states with the ground. The effectiveness of the proposed foot structure is verified experimentally.